If <symbol_name> is in the symbol table of the DLL a pointer to the <symbol_name> is returned. Otherwise, returns 0. Set the ignore_errors flag to supress logging errors if symbol_name isn't found. This is nice if you just want to probe a dll to see what's available, since missing functions in that case aren't really errors.More...

Private Methods

Returns a pointer to a string explaining why <symbol> or <open> failed. This is used internal to print out the error to the log, but since this object is shared, we can't store or return the error to the caller.More...

Static Private Attributes

Keeps track of whether or not open() has ever been called. This helps get around problem on Linux, and perhaps other OS's, that seg-fault if dlerror() is called before the ld library has been initialized by a call to dlopen().More...

Detailed Description

Provides an abstract interface for handling various DLL operations.

This class is an wrapper over the various methods for utilizing a dynamically linked library (DLL), which is called a shared library on some platforms. It is refcounted and managed by ACE_DLL_Manager, so there will only be a single instance of this class for each dll loaded, no matter how many instances of ACE_DLL an application has open. Operations <open>, <close>, and <symbol> have been implemented to help opening/closing and extracting symbol information from a DLL, respectively.

Most of this class came from the original ACE_DLL class. ACE_DLL is now just an interface that passed all it's calls either directly or via ACE_DLL_Manager to this class for execution.

Returns a pointer to a string explaining why <symbol> or <open> failed. This is used internal to print out the error to the log, but since this object is shared, we can't store or return the error to the caller.

This method opens and dynamically links <dll_name>. The default mode is <RTLD_LAZY>, which loads identifier symbols but not the symbols for functions, which are loaded dynamically on-demand. Other supported modes include: <RTLD_NOW>, which performs all necessary relocations when <dll_name> is first loaded and <RTLD_GLOBAL>, which makes symbols available for relocation processing of any other DLLs. Returns -1 on failure and 0 on success.

If <symbol_name> is in the symbol table of the DLL a pointer to the <symbol_name> is returned. Otherwise, returns 0. Set the ignore_errors flag to supress logging errors if symbol_name isn't found. This is nice if you just want to probe a dll to see what's available, since missing functions in that case aren't really errors.

Keeps track of whether or not open() has ever been called. This helps get around problem on Linux, and perhaps other OS's, that seg-fault if dlerror() is called before the ld library has been initialized by a call to dlopen().